PSU high frequency transformers how to read and find Specifications

Thread Starter

Nelson2001

Joined Nov 10, 2011
27
Can You help me I want to lean about high frequency transformers in psu, but I was unable to find the datasheets with the windings. this is my psu. thank tou in advance.
The transformers are tm8350-erl35, 8350 ee16dx, 8350ee19dx.
I want to undertand how to find specifications and datasheet of high frequency power transformers to test the windings.
Some book or datasheets are welcome. Thank you again
P1060551.JPG
 

DickCappels

Joined Aug 21, 2008
10,246
Those are very likely to be custom transformers and inductors. Is there the name of the manufacturer printed on them anywhere?
 

ian field

Joined Oct 27, 2012
6,536
Custom ones. Buy an Inductance meter first.
The inductance is likely to be pretty low and some commercial meters struggle that low.

An inductance bridge might be needed - then we're talking laboratory grade instruments at laboratory grade prices.

For all intents and purposes, a shorted turn tester might be nearer the mark.

The Australian Dick Smith Electronics did such an instrument for testing TV flyback transformers - but even that shows a short on very low inductance.

The kit probably isn't available anymore, but the schematic is floating about in various places online.
 

MaxHeadRoom

Joined Jul 18, 2013
28,829
The inductance is likely to be pretty low and some commercial meters struggle that low.
An inductance bridge might be needed - then we're talking laboratory grade instruments at laboratory grade prices.
For all intents and purposes, a shorted turn tester might be nearer the mark.
The Australian Dick Smith Electronics did such an instrument for testing TV flyback transformers - but even that shows a short on very low inductance.
The kit probably isn't available anymore, but the schematic is floating about in various places online.
I picked up a cheap Chinese RC meter off ebay for $15.00 I checked it and it is quite accurate, and a wide/dual range.
I built one of the Dick Smith HOT testers eons ago from his print, but it shows go/no go, no actual value displayed.
Max.
 

ian field

Joined Oct 27, 2012
6,536
I picked up a cheap Chinese RC meter off ebay for $15.00 I checked it and it is quite accurate, and a wide/dual range.
I built one of the Dick Smith HOT testers eons ago from his print, but it shows go/no go, no actual value displayed.
Max.
The one I bought pings the inductor with an oscillator built round a comparator.

The ringing pulses are clocked through a SIPO shift register - the more times it rings, the more LEDs light up.
 

Thread Starter

Nelson2001

Joined Nov 10, 2011
27
Those are very likely to be custom transformers and inductors. Is there the name of the manufacturer printed on them anywhere?
May be I don't know how to test the primary side (4 pins) and the secundary side(2 pins or more). This is the problem. I found in another PSU the primary side 4 pins (2 primary ) and 2 pins in the secundary part. It was easy, because one of the primary side was broke. So the psu never work and the windings are very hard to fix.
In this case I found 4 or more pins in primary side and 3 or more pins in the secundary side. I only want to test continuity to be sure the problem is another one.

For example i looking something like this to be sure the windings are not open.
 

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